“I was eleven and could play perhaps the first page and a half. I’d no idea what the piece was about, but what I could read and play fascinated me,” Hélène Grimaud describes her early contact with the piece that is central to the present release, a piece she first encountered when she was still practically a child. “Alban Berg’s sonata”, she continues, “was the starting point for a programme that seems to trace an arbitrary line through the history of music.” And yet she identifies subtle links that take her on a geographical journey through the former Austro-Hungarian Empire, although she admits that “Mozart’s Salzburg did not officially belong to Austria, and Bartók would have strongly resisted this act of appropriation. But somehow Mozart’s music anticipates much that later returns in the music of Austro-Hungary, in Liszt and even in Berg, where it comes to full fruition.”

Resonances can be identified. Echoes and pre-echoes, fascinating historical links that come together in Berg’s sonata. The Op. 1 of the Viennese master of atonality is nominally in B minor, but it already explores the very limits of tonality. It serves as the conceptual starting point and effective culmination of the musical journey that Hélène Grimaud under­takes with her listeners. And all roads lead to the harmonic and thematic distillation that Schoenberg’s pupil achieved with this “apprentice piece” of his: Berg’s sonata concentrates in a single movement everything that constitutes a Classical sonata movement and does so, moreover, in the simplest manner imaginable.

But the architectural rigour – an “echo” of the Classical structure that Berg learnt from his teacher – goes hand in hand with a wealth of ideas and an emotional openness that are rarely found in music of the early modern period, a period that reaches its first real high point in this work.

“One assumes that a piece with the opus number one”, says Hélène Grimaud, “must be an early work, but the truth is that Berg’s sonata is the perfect incarnation of what he could bring to the world. It’s an extreme expression of something that seems to come from the soul, involving no calculation and yet resulting in a piece of an unfathomabbly lucid structure.”

It was in 2009 that Hélène Grimaud rediscovered the copy of the score that she had retained from her childhood like some oddly fascinating treasure. Now an internationally acclaimed pianist, she re-read the piece that had once seemed so mysterious and that her teacher Pierre Barbizet had filled with many colourful notes and an affectionate “list of contents” stuck to the front endpapers. It was now revealed with the immediacy of a dramatic scene from a Romantic opera. “It’s a music drama cast in the miniature form of a single-movement sonata,” says the pianist.

This brings us neatly on to the only piano sonata by that sorcerer among Romantic pianists, a work that is likewise in B minor: “Franz Liszt too wrote a single-movement sonata,” says Hélène Grimaud, “albeit on a vast – let’s admit it, ‘Wagnerian’ – scale. From a structural point of view, the movements of a multi-sectional sonata in first-movement sonata form, with exposition, development section, recapitulation and coda, have merged together. Once again we have echoes of something that is familiar, but redefined and reordered and concentrated in one vast formal structure. And once again the question isn’t that of the composer’s mastery in erecting such a complex edifice. The fact that Liszt is in total control of the musical structure says nothing about the equally highly developed mastery of expression. The result is a music drama guided by the possibilities of the piano, a sonata that is as theatrical as a sonata can be, operatic in an instrumental sense. Let’s not forget the musico-historical component: Wagner wouldn’t have written his operas if Liszt hadn’t existed. At least not in the way he wrote them.”

With the Liszt Sonata the pianist becomes a stage director, a role she sees as an artistic challenge. “Historically speaking, this leads us back to Mozart. He too writes operatic scenes for his instrument, giving it recitatives and arias to sing. He extracts everything from the possibilities of the piano. In terms of his period – and this links him to Liszt and Berg – he’s an extremist in matters of expression, a point that made him so interesting to Beethoven: the middle movements of Mozart’s A minor Sonata and Beethoven’s Sonata op. 31 no. 2 (‘The Tempest’) are as related as any brother and sister. Mozart’s sonata teems with things that were to come later; and it speaks a subjective language.”

The music of Béla Bartók strikes us like that of Liszt and Berg, only in a different way, for he tried to define the linguistic element in music even more concretely than his predecessors. Not only within the confines of the Austro-Hungarian Empire but also after its collapse, he set out in search of true folk music, the authentic language of human beings, and made it the source of his inspiration. It appears in works such as the Romanian Folk Dances not as an echo but as something direct and undistorted. At the end of our musical journey to eastern Europe, we find ourselves listening more closely than ever to the most immediate expression of people singing and dancing, at the point where the expression of the subject is again subsumed by the collective understanding.